* [RFC 1/2] kvm: Mechanism to copy host timekeeping parameters into guest.
2019-09-20 6:27 [RFC 0/2] kvm: Use host timekeeping in guest Suleiman Souhlal
@ 2019-09-20 6:27 ` Suleiman Souhlal
2019-09-20 6:27 ` [RFC 2/2] x86/kvmclock: Use host timekeeping Suleiman Souhlal
2019-09-20 7:48 ` [RFC 0/2] kvm: Use host timekeeping in guest Paolo Bonzini
2 siblings, 0 replies; 9+ messages in thread
From: Suleiman Souhlal @ 2019-09-20 6:27 UTC (permalink / raw)
To: pbonzini, rkrcmar, tglx
Cc: john.stultz, sboyd, linux-kernel, kvm, Suleiman Souhlal
This is used to synchronize time between host and guest.
The guest can request the (guest) physical address it wants the
data in through the MSR_KVM_TIMEKEEPER_EN MSR.
We maintain a shadow copy of the timekeeper that gets updated
whenever the timekeeper gets updated, and then copied into the
guest.
It currently assumes the host timekeeper is "tsc".
Signed-off-by: Suleiman Souhlal <suleiman@google.com>
---
arch/x86/include/asm/kvm_host.h | 3 +
arch/x86/include/asm/pvclock-abi.h | 27 ++++++
arch/x86/include/uapi/asm/kvm_para.h | 1 +
arch/x86/kvm/x86.c | 121 +++++++++++++++++++++++++++
4 files changed, 152 insertions(+)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index bdc16b0aa7c6..b1b4c3a80b8d 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -666,7 +666,10 @@ struct kvm_vcpu_arch {
struct pvclock_vcpu_time_info hv_clock;
unsigned int hw_tsc_khz;
struct gfn_to_hva_cache pv_time;
+ struct gfn_to_hva_cache pv_timekeeper_g2h;
+ struct pvclock_timekeeper pv_timekeeper;
bool pv_time_enabled;
+ bool pv_timekeeper_enabled;
/* set guest stopped flag in pvclock flags field */
bool pvclock_set_guest_stopped_request;
diff --git a/arch/x86/include/asm/pvclock-abi.h b/arch/x86/include/asm/pvclock-abi.h
index 1436226efe3e..2809008b9b26 100644
--- a/arch/x86/include/asm/pvclock-abi.h
+++ b/arch/x86/include/asm/pvclock-abi.h
@@ -40,6 +40,33 @@ struct pvclock_wall_clock {
u32 nsec;
} __attribute__((__packed__));
+struct pvclock_read_base {
+ u64 mask;
+ u64 cycle_last;
+ u32 mult;
+ u32 shift;
+ u64 xtime_nsec;
+ u64 base;
+} __attribute__((__packed__));
+
+struct pvclock_timekeeper {
+ u64 gen;
+ u64 flags;
+ struct pvclock_read_base tkr_mono;
+ struct pvclock_read_base tkr_raw;
+ u64 xtime_sec;
+ u64 ktime_sec;
+ u64 wall_to_monotonic_sec;
+ u64 wall_to_monotonic_nsec;
+ u64 offs_real;
+ u64 offs_boot;
+ u64 offs_tai;
+ u64 raw_sec;
+ u64 tsc_offset;
+} __attribute__((__packed__));
+
+#define PVCLOCK_TIMEKEEPER_ENABLED (1 << 0)
+
#define PVCLOCK_TSC_STABLE_BIT (1 << 0)
#define PVCLOCK_GUEST_STOPPED (1 << 1)
/* PVCLOCK_COUNTS_FROM_ZERO broke ABI and can't be used anymore. */
diff --git a/arch/x86/include/uapi/asm/kvm_para.h b/arch/x86/include/uapi/asm/kvm_para.h
index 2a8e0b6b9805..3ebb1d87db3a 100644
--- a/arch/x86/include/uapi/asm/kvm_para.h
+++ b/arch/x86/include/uapi/asm/kvm_para.h
@@ -50,6 +50,7 @@
#define MSR_KVM_STEAL_TIME 0x4b564d03
#define MSR_KVM_PV_EOI_EN 0x4b564d04
#define MSR_KVM_POLL_CONTROL 0x4b564d05
+#define MSR_KVM_TIMEKEEPER_EN 0x4b564d06
struct kvm_steal_time {
__u64 steal;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 91602d310a3f..06a940a74005 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -157,6 +157,8 @@ module_param(force_emulation_prefix, bool, S_IRUGO);
int __read_mostly pi_inject_timer = -1;
module_param(pi_inject_timer, bint, S_IRUGO | S_IWUSR);
+static atomic_t pv_timekeepers_nr;
+
#define KVM_NR_SHARED_MSRS 16
struct kvm_shared_msrs_global {
@@ -2621,6 +2623,16 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
break;
}
+ case MSR_KVM_TIMEKEEPER_EN:
+ if (kvm_gfn_to_hva_cache_init(vcpu->kvm,
+ &vcpu->arch.pv_timekeeper_g2h, data,
+ sizeof(struct pvclock_timekeeper)))
+ vcpu->arch.pv_timekeeper_enabled = false;
+ else {
+ vcpu->arch.pv_timekeeper_enabled = true;
+ atomic_inc(&pv_timekeepers_nr);
+ }
+ break;
case MSR_KVM_ASYNC_PF_EN:
if (kvm_pv_enable_async_pf(vcpu, data))
return 1;
@@ -6965,6 +6977,109 @@ static struct perf_guest_info_callbacks kvm_guest_cbs = {
.handle_intel_pt_intr = kvm_handle_intel_pt_intr,
};
+static DEFINE_SPINLOCK(shadow_pvtk_lock);
+static struct pvclock_timekeeper shadow_pvtk;
+
+static void
+pvclock_copy_read_base(struct pvclock_read_base *pvtkr,
+ struct tk_read_base *tkr)
+{
+ pvtkr->cycle_last = tkr->cycle_last;
+ pvtkr->mult = tkr->mult;
+ pvtkr->shift = tkr->shift;
+ pvtkr->mask = tkr->mask;
+ pvtkr->xtime_nsec = tkr->xtime_nsec;
+ pvtkr->base = tkr->base;
+}
+
+static void
+kvm_copy_into_pvtk(struct kvm_vcpu *vcpu)
+{
+ struct pvclock_timekeeper *pvtk;
+ unsigned long flags;
+
+ if (!vcpu->arch.pv_timekeeper_enabled)
+ return;
+
+ pvtk = &vcpu->arch.pv_timekeeper;
+ if (pvclock_gtod_data.clock.vclock_mode == VCLOCK_TSC) {
+ pvtk->flags |= PVCLOCK_TIMEKEEPER_ENABLED;
+ spin_lock_irqsave(&shadow_pvtk_lock, flags);
+ pvtk->tkr_mono = shadow_pvtk.tkr_mono;
+ pvtk->tkr_raw = shadow_pvtk.tkr_raw;
+
+ pvtk->xtime_sec = shadow_pvtk.xtime_sec;
+ pvtk->ktime_sec = shadow_pvtk.ktime_sec;
+ pvtk->wall_to_monotonic_sec =
+ shadow_pvtk.wall_to_monotonic_sec;
+ pvtk->wall_to_monotonic_nsec =
+ shadow_pvtk.wall_to_monotonic_nsec;
+ pvtk->offs_real = shadow_pvtk.offs_real;
+ pvtk->offs_boot = shadow_pvtk.offs_boot;
+ pvtk->offs_tai = shadow_pvtk.offs_tai;
+ pvtk->raw_sec = shadow_pvtk.raw_sec;
+ spin_unlock_irqrestore(&shadow_pvtk_lock, flags);
+
+ pvtk->tsc_offset = kvm_x86_ops->read_l1_tsc_offset(vcpu);
+ } else
+ pvtk->flags &= ~PVCLOCK_TIMEKEEPER_ENABLED;
+
+ BUILD_BUG_ON(offsetof(struct pvclock_timekeeper, gen) != 0);
+
+ /*
+ * Make the gen count odd to indicate we are in the process of
+ * updating.
+ */
+ vcpu->arch.pv_timekeeper.gen++;
+ vcpu->arch.pv_timekeeper.gen |= 1;
+
+ /*
+ * See comment in kvm_guest_time_update() for why we have to do
+ * multiple writes.
+ */
+ kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.pv_timekeeper_g2h,
+ &vcpu->arch.pv_timekeeper, sizeof(vcpu->arch.pv_timekeeper.gen));
+
+ smp_wmb();
+
+ kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.pv_timekeeper_g2h,
+ &vcpu->arch.pv_timekeeper, sizeof(vcpu->arch.pv_timekeeper));
+
+ smp_wmb();
+
+ vcpu->arch.pv_timekeeper.gen++;
+
+ kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.pv_timekeeper_g2h,
+ &vcpu->arch.pv_timekeeper, sizeof(vcpu->arch.pv_timekeeper.gen));
+}
+
+static void
+update_shadow_pvtk(struct timekeeper *tk)
+{
+ struct pvclock_timekeeper *pvtk;
+ unsigned long flags;
+
+ pvtk = &shadow_pvtk;
+
+ if (atomic_read(&pv_timekeepers_nr) == 0 ||
+ pvclock_gtod_data.clock.vclock_mode != VCLOCK_TSC)
+ return;
+
+ spin_lock_irqsave(&shadow_pvtk_lock, flags);
+ pvclock_copy_read_base(&pvtk->tkr_mono, &tk->tkr_mono);
+ pvclock_copy_read_base(&pvtk->tkr_raw, &tk->tkr_raw);
+
+ pvtk->xtime_sec = tk->xtime_sec;
+ pvtk->ktime_sec = tk->ktime_sec;
+ pvtk->wall_to_monotonic_sec = tk->wall_to_monotonic.tv_sec;
+ pvtk->wall_to_monotonic_nsec = tk->wall_to_monotonic.tv_nsec;
+ pvtk->offs_real = tk->offs_real;
+ pvtk->offs_boot = tk->offs_boot;
+ pvtk->offs_tai = tk->offs_tai;
+ pvtk->raw_sec = tk->raw_sec;
+ spin_unlock_irqrestore(&shadow_pvtk_lock, flags);
+}
+
#ifdef CONFIG_X86_64
static void pvclock_gtod_update_fn(struct work_struct *work)
{
@@ -6993,6 +7108,7 @@ static int pvclock_gtod_notify(struct notifier_block *nb, unsigned long unused,
struct timekeeper *tk = priv;
update_pvclock_gtod(tk);
+ update_shadow_pvtk(tk);
/* disable master clock if host does not trust, or does not
* use, TSC based clocksource.
@@ -7809,6 +7925,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
bool req_immediate_exit = false;
+ kvm_copy_into_pvtk(vcpu);
+
if (kvm_request_pending(vcpu)) {
if (kvm_check_request(KVM_REQ_GET_VMCS12_PAGES, vcpu))
kvm_x86_ops->get_vmcs12_pages(vcpu);
@@ -8891,6 +9009,9 @@ void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
kvmclock_reset(vcpu);
+ if (vcpu->arch.pv_timekeeper_enabled)
+ atomic_dec(&pv_timekeepers_nr);
+
kvm_x86_ops->vcpu_free(vcpu);
free_cpumask_var(wbinvd_dirty_mask);
}
--
2.23.0.237.gc6a4ce50a0-goog
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [RFC 2/2] x86/kvmclock: Use host timekeeping.
2019-09-20 6:27 [RFC 0/2] kvm: Use host timekeeping in guest Suleiman Souhlal
2019-09-20 6:27 ` [RFC 1/2] kvm: Mechanism to copy host timekeeping parameters into guest Suleiman Souhlal
@ 2019-09-20 6:27 ` Suleiman Souhlal
2019-09-20 13:33 ` Vitaly Kuznetsov
2019-09-20 7:48 ` [RFC 0/2] kvm: Use host timekeeping in guest Paolo Bonzini
2 siblings, 1 reply; 9+ messages in thread
From: Suleiman Souhlal @ 2019-09-20 6:27 UTC (permalink / raw)
To: pbonzini, rkrcmar, tglx
Cc: john.stultz, sboyd, linux-kernel, kvm, Suleiman Souhlal
When CONFIG_KVMCLOCK_HOST_TIMEKEEPING is enabled, and the host
supports it, update our timekeeping parameters to be the same as
the host. This lets us have our time synchronized with the host's,
even in the presence of host NTP or suspend.
When enabled, kvmclock uses raw tsc instead of pvclock.
When enabled, syscalls that can change time, such as settimeofday(2)
or adj_timex(2) are disabled in the guest.
Signed-off-by: Suleiman Souhlal <suleiman@google.com>
---
arch/x86/Kconfig | 9 +++
arch/x86/include/asm/kvmclock.h | 2 +
arch/x86/kernel/kvmclock.c | 127 +++++++++++++++++++++++++++++++-
kernel/time/timekeeping.c | 21 ++++++
4 files changed, 155 insertions(+), 4 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 4195f44c6a09..37299377d9d7 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -837,6 +837,15 @@ config PARAVIRT_TIME_ACCOUNTING
config PARAVIRT_CLOCK
bool
+config KVMCLOCK_HOST_TIMEKEEPING
+ bool "kvmclock uses host timekeeping"
+ depends on KVM_GUEST
+ ---help---
+ Select this option to make the guest use the same timekeeping
+ parameters as the host. This means that time will be almost
+ exactly the same between the two. Only works if the host uses "tsc"
+ clocksource.
+
config JAILHOUSE_GUEST
bool "Jailhouse non-root cell support"
depends on X86_64 && PCI
diff --git a/arch/x86/include/asm/kvmclock.h b/arch/x86/include/asm/kvmclock.h
index eceea9299097..cad7eae62b54 100644
--- a/arch/x86/include/asm/kvmclock.h
+++ b/arch/x86/include/asm/kvmclock.h
@@ -4,4 +4,6 @@
extern struct clocksource kvm_clock;
+bool kvm_clock_copy_into_tk(struct timekeeper *tk);
+
#endif /* _ASM_X86_KVM_CLOCK_H */
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index 904494b924c1..e3a33dcaffc8 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -16,6 +16,7 @@
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/set_memory.h>
+#include <linux/timekeeper_internal.h>
#include <asm/hypervisor.h>
#include <asm/mem_encrypt.h>
@@ -29,6 +30,9 @@ static int msr_kvm_system_time __ro_after_init = MSR_KVM_SYSTEM_TIME;
static int msr_kvm_wall_clock __ro_after_init = MSR_KVM_WALL_CLOCK;
static u64 kvm_sched_clock_offset __ro_after_init;
+static bool pv_timekeeper_enabled;
+static bool pv_timekeeper_present;
+
static int __init parse_no_kvmclock(char *arg)
{
kvmclock = 0;
@@ -54,6 +58,8 @@ static struct pvclock_wall_clock wall_clock __bss_decrypted;
static DEFINE_PER_CPU(struct pvclock_vsyscall_time_info *, hv_clock_per_cpu);
static struct pvclock_vsyscall_time_info *hvclock_mem;
+struct pvclock_timekeeper pv_timekeeper;
+
static inline struct pvclock_vcpu_time_info *this_cpu_pvti(void)
{
return &this_cpu_read(hv_clock_per_cpu)->pvti;
@@ -94,7 +100,10 @@ static u64 kvm_clock_read(void)
static u64 kvm_clock_get_cycles(struct clocksource *cs)
{
- return kvm_clock_read();
+ if (pv_timekeeper_present)
+ return rdtsc_ordered();
+ else
+ return kvm_clock_read();
}
static u64 kvm_sched_clock_read(void)
@@ -159,9 +168,26 @@ bool kvm_check_and_clear_guest_paused(void)
return ret;
}
+int
+kvm_clock_enable(struct clocksource *cs)
+{
+ if (pv_timekeeper_present)
+ pv_timekeeper_enabled = 1;
+
+ return 0;
+}
+
+void
+kvm_clock_disable(struct clocksource *cs)
+{
+ pv_timekeeper_enabled = 0;
+}
+
struct clocksource kvm_clock = {
.name = "kvm-clock",
.read = kvm_clock_get_cycles,
+ .enable = kvm_clock_enable,
+ .disable = kvm_clock_disable,
.rating = 400,
.mask = CLOCKSOURCE_MASK(64),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
@@ -197,6 +223,86 @@ static void kvm_setup_secondary_clock(void)
}
#endif
+#ifdef CONFIG_KVMCLOCK_HOST_TIMEKEEPING
+static void
+pvclock_copy_into_read_base(struct pvclock_timekeeper *pvtk,
+ struct tk_read_base *tkr, struct pvclock_read_base *pvtkr)
+{
+ int shift_diff;
+
+ tkr->mask = pvtkr->mask;
+ tkr->cycle_last = pvtkr->cycle_last + pvtk->tsc_offset;
+ tkr->mult = pvtkr->mult;
+ shift_diff = tkr->shift - pvtkr->shift;
+ tkr->shift = pvtkr->shift;
+ tkr->xtime_nsec = pvtkr->xtime_nsec;
+ tkr->base = pvtkr->base;
+}
+
+static u64
+pvtk_read_begin(struct pvclock_timekeeper *pvtk)
+{
+ u64 gen;
+
+ gen = pvtk->gen & ~1;
+ /* Make sure that the gen count is read before the data. */
+ virt_rmb();
+
+ return gen;
+}
+
+static bool
+pvtk_read_retry(struct pvclock_timekeeper *pvtk, u64 gen)
+{
+ /* Make sure that the gen count is re-read after the data. */
+ virt_rmb();
+ return unlikely(gen != pvtk->gen);
+}
+
+bool
+kvm_clock_copy_into_tk(struct timekeeper *tk)
+{
+ struct pvclock_timekeeper *pvtk;
+ u64 gen;
+
+ if (!pv_timekeeper_enabled)
+ return false;
+
+ pvtk = &pv_timekeeper;
+ do {
+ gen = pvtk_read_begin(pvtk);
+ if (!(pv_timekeeper.flags & PVCLOCK_TIMEKEEPER_ENABLED))
+ return false;
+
+ pvclock_copy_into_read_base(pvtk, &tk->tkr_mono,
+ &pvtk->tkr_mono);
+ pvclock_copy_into_read_base(pvtk, &tk->tkr_raw, &pvtk->tkr_raw);
+
+ tk->xtime_sec = pvtk->xtime_sec;
+ tk->ktime_sec = pvtk->ktime_sec;
+ tk->wall_to_monotonic.tv_sec = pvtk->wall_to_monotonic_sec;
+ tk->wall_to_monotonic.tv_nsec = pvtk->wall_to_monotonic_nsec;
+ tk->offs_real = pvtk->offs_real;
+ tk->offs_boot = pvtk->offs_boot;
+ tk->offs_tai = pvtk->offs_tai;
+ tk->raw_sec = pvtk->raw_sec;
+ } while (pvtk_read_retry(pvtk, gen));
+
+ return true;
+}
+
+static void
+kvm_register_timekeeper(void)
+{
+ unsigned long pa;
+
+ pa = __pa(&pv_timekeeper);
+ wrmsrl(MSR_KVM_TIMEKEEPER_EN, pa);
+ if (pv_timekeeper.flags & PVCLOCK_TIMEKEEPER_ENABLED)
+ pv_timekeeper_present = 1;
+}
+#endif /* CONFIG_KVMCLOCK_HOST_TIMEKEEPING */
+
/*
* After the clock is registered, the host will keep writing to the
* registered memory location. If the guest happens to shutdown, this memory
@@ -271,8 +377,10 @@ static int __init kvm_setup_vsyscall_timeinfo(void)
flags = pvclock_read_flags(&hv_clock_boot[0].pvti);
if (!(flags & PVCLOCK_TSC_STABLE_BIT))
return 0;
-
- kvm_clock.archdata.vclock_mode = VCLOCK_PVCLOCK;
+ if (pv_timekeeper_present)
+ kvm_clock.archdata.vclock_mode = VCLOCK_TSC;
+ else
+ kvm_clock.archdata.vclock_mode = VCLOCK_PVCLOCK;
#endif
kvmclock_init_mem();
@@ -312,6 +420,10 @@ void __init kvmclock_init(void)
if (!kvm_para_available() || !kvmclock)
return;
+#ifdef CONFIG_KVMCLOCK_HOST_TIMEKEEPING
+ kvm_register_timekeeper();
+#endif
+
if (kvm_para_has_feature(KVM_FEATURE_CLOCKSOURCE2)) {
msr_kvm_system_time = MSR_KVM_SYSTEM_TIME_NEW;
msr_kvm_wall_clock = MSR_KVM_WALL_CLOCK_NEW;
@@ -360,11 +472,18 @@ void __init kvmclock_init(void)
* can use TSC as clocksource.
*
*/
+#ifndef CONFIG_KVMCLOCK_HOST_TIMEKEEPING
if (boot_cpu_has(X86_FEATURE_CONSTANT_TSC) &&
boot_cpu_has(X86_FEATURE_NONSTOP_TSC) &&
!check_tsc_unstable())
kvm_clock.rating = 299;
+#endif
+
+ if (pv_timekeeper_present)
+ clocksource_register_khz(&kvm_clock,
+ pvclock_tsc_khz(this_cpu_pvti()));
+ else
+ clocksource_register_hz(&kvm_clock, NSEC_PER_SEC);
- clocksource_register_hz(&kvm_clock, NSEC_PER_SEC);
pv_info.name = "KVM";
}
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index ca69290bee2a..c6e4785babb1 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -23,6 +23,10 @@
#include <linux/compiler.h>
#include <linux/audit.h>
+#ifdef CONFIG_KVMCLOCK_HOST_TIMEKEEPING
+#include <asm/kvmclock.h>
+#endif
+
#include "tick-internal.h"
#include "ntp_internal.h"
#include "timekeeping_internal.h"
@@ -1223,6 +1227,7 @@ EXPORT_SYMBOL_GPL(get_device_system_crosststamp);
*/
int do_settimeofday64(const struct timespec64 *ts)
{
+#ifndef CONFIG_KVMCLOCK_HOST_TIMEKEEPING
struct timekeeper *tk = &tk_core.timekeeper;
struct timespec64 ts_delta, xt;
unsigned long flags;
@@ -1261,9 +1266,13 @@ int do_settimeofday64(const struct timespec64 *ts)
audit_tk_injoffset(ts_delta);
return ret;
+#else /* CONFIG_KVMCLOCK_HOST_TIMEKEEPING */
+ return -EINVAL;
+#endif /* CONFIG_KVMCLOCK_HOST_TIMEKEEPING */
}
EXPORT_SYMBOL(do_settimeofday64);
+#ifndef CONFIG_KVMCLOCK_HOST_TIMEKEEPING
/**
* timekeeping_inject_offset - Adds or subtracts from the current time.
* @tv: pointer to the timespec variable containing the offset
@@ -1307,6 +1316,7 @@ static int timekeeping_inject_offset(const struct timespec64 *ts)
return ret;
}
+#endif /* CONFIG_KVMCLOCK_HOST_TIMEKEEPING */
/*
* Indicates if there is an offset between the system clock and the hardware
@@ -1332,6 +1342,7 @@ int persistent_clock_is_local;
*/
void timekeeping_warp_clock(void)
{
+#ifndef CONFIG_KVMCLOCK_HOST_TIMEKEEPING
if (sys_tz.tz_minuteswest != 0) {
struct timespec64 adjust;
@@ -1340,6 +1351,7 @@ void timekeeping_warp_clock(void)
adjust.tv_nsec = 0;
timekeeping_inject_offset(&adjust);
}
+#endif /* CONFIG_KVMCLOCK_HOST_TIMEKEEPING */
}
/**
@@ -2107,6 +2119,9 @@ static void timekeeping_advance(enum timekeeping_adv_mode mode)
clock_set |= accumulate_nsecs_to_secs(tk);
write_seqcount_begin(&tk_core.seq);
+#ifdef CONFIG_KVMCLOCK_HOST_TIMEKEEPING
+ kvm_clock_copy_into_tk(tk);
+#endif
/*
* Update the real timekeeper.
*
@@ -2241,6 +2256,7 @@ ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq, ktime_t *offs_real,
return base;
}
+#ifndef CONFIG_KVMCLOCK_HOST_TIMEKEEPING
/**
* timekeeping_validate_timex - Ensures the timex is ok for use in do_adjtimex
*/
@@ -2305,6 +2321,7 @@ static int timekeeping_validate_timex(const struct __kernel_timex *txc)
return 0;
}
+#endif /* CONFIG_KVMCLOCK_HOST_TIMEKEEPING */
/**
@@ -2312,6 +2329,7 @@ static int timekeeping_validate_timex(const struct __kernel_timex *txc)
*/
int do_adjtimex(struct __kernel_timex *txc)
{
+#ifndef CONFIG_KVMCLOCK_HOST_TIMEKEEPING
struct timekeeper *tk = &tk_core.timekeeper;
struct audit_ntp_data ad;
unsigned long flags;
@@ -2368,6 +2386,9 @@ int do_adjtimex(struct __kernel_timex *txc)
ntp_notify_cmos_timer();
return ret;
+#else /* CONFIG_KVMCLOCK_HOST_TIMEKEEPING */
+ return -EINVAL;
+#endif /* CONFIG_KVMCLOCK_HOST_TIMEKEEPING */
}
#ifdef CONFIG_NTP_PPS
--
2.23.0.237.gc6a4ce50a0-goog
^ permalink raw reply related [flat|nested] 9+ messages in thread